Source of it – roots of evil

It started a long time ago, but no one felt responsible. Things started to turn dark, rotting even. In the beginning it was liveable, but not any more. More and more strange phenomena occurred on earth. Animals became hostile and left their natural surroundings. Soil turned into a thick dark sludge. Natural resources such as water and small pieces of wood have become peoples highest valued possessions. The environment is almost depleted. The corruption and decay is not stopping and no one knows what to do. No one even knows what the evil source behind all of this is. Four heroes living humble lives realise they have to collaborate, find the source of it and face it in a big final confrontation. You have taken it upon yourselves to save the world. The world is in your hands!